7209-BECBM bearing: complete specifications & equivalents

Specification table

Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018)) · extracted 2026-09-27

Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018)); SKF® and SKF Explorer® are trademarks of AB SKF, used here for identification only — mpnbase is not an authorized SKF distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at skf.com.

Cross references & equivalents

Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.

How the 7209-BECBM model number is decoded

7209 BECBM is SKF's 45 mm-bore single-row angular-contact ball bearing in the 7200 series, nominal 40° (B) contact angle, 45×85×19 mm to the ISO dimension plan. 40° contact angle (suffix B): the steep standard single-row angle, giving the highest axial capacity at the cost of speed, with a recommended load ratio Fa/Fr ≥ 1. E marks the optimized internal design with an enhanced ball complement and race geometry. machined brass cage, ball-centred (suffix M), the choice for high speed, marginal lubrication and shock duty. CB means universally matchable with Normal axial internal clearance: the two side faces are ground so any two units form DB (back-to-back), DF (face-to-face) or DT (tandem) sets without regrinding. Envelope 45×85×19 mm (1.772×3.346×0.748 in), 20.0 mm radial section height, C 38 kN, C0 28.5 kN, Pu 1.22 kN.reference speed 9,500 r/min (thermal) and limiting speed 12,000 r/min (mechanical), catalogue mass 420 g. Load balance: C0 28.5 kN against C 38 kN gives a 0.75 ratio, typical of a steep-angle axial-oriented design; Pu 1.22 kN enters the SKF adjusted-life equation rather than the basic rating life. Sizing arithmetic on the 45 mm bore: 38 kN C divided by the 20.0 mm radial section height gives 1.9 kN per section millimetre; the 420 g mass and 3 % Pu/C share frame the light-load floor for the adjusted-life check. Bore-to-OD planning: OD 85 over bore 45 is a 1.89× step for this size, and the 19 mm width gives a bore/width ratio of 2.37; use these ratios when housing space around the 45 mm shaft is the first constraint. Cage detail specific to this order number: the M cage is a one-piece machined brass window cage centred on the balls, chosen for high speeds, thin-film lubrication and shock loads; it is heavier and stiffer than the stamped Y-cage execution and tolerates interrupted oil supply far better than the PA66 or PEEK alternatives. Do not substitute the stamped-brass BECBY order number expecting identical cage behaviour.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• DB pairs give the highest moment stiffness, DF pairs tolerate misalignment and thermal expansion better, DT shares heavy one-direction thrust; choose from the shaft thermal calculation rather than by habit.
• Fillet radii must clear the chamfer so the 19 mm-wide ring seats square; an oversized shaft radius creates point contact on the ring face.
• Keep the load ratio in the SKF design range: Fa/Fr ≥ 1 for this angle; below it the balls unload the contact ellipse and skid, which is why the catalogue insists on a minimum axial load (Fam ≈ A·(n·dm/1000)²) at high speed.
• At 45 mm bore the k5 seat assumes a steel shaft and housing; aluminium housings grow faster with temperature, so re-check the outer-ring setting when the case is non-ferrous.
• The steep 40° angle of 7209-BECBM favours thrust-heavy combined loads; for a predominantly radial high-speed position the 25° ACCBM execution of the same size is the alternative order number.
• Universally matchable BECBM bearings arrive ready for set mounting, not preloaded sets: preload results from how the set is clamped, so follow the SKF stand-off-ring and nut-torque procedure.